1/*
2 * Allwinner EMAC Fast Ethernet driver for Linux.
3 *
4 * Copyright 2012-2013 Stefan Roese <sr@denx.de>
5 * Copyright 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
6 *
7 * Based on the Linux driver provided by Allwinner:
8 * Copyright (C) 1997  Sten Wang
9 *
10 * This file is licensed under the terms of the GNU General Public
11 * License version 2. This program is licensed "as is" without any
12 * warranty of any kind, whether express or implied.
13 */
14
15#include <linux/clk.h>
16#include <linux/etherdevice.h>
17#include <linux/ethtool.h>
18#include <linux/gpio.h>
19#include <linux/interrupt.h>
20#include <linux/irq.h>
21#include <linux/mii.h>
22#include <linux/module.h>
23#include <linux/netdevice.h>
24#include <linux/of_address.h>
25#include <linux/of_irq.h>
26#include <linux/of_mdio.h>
27#include <linux/of_net.h>
28#include <linux/of_platform.h>
29#include <linux/platform_device.h>
30#include <linux/phy.h>
31#include <linux/soc/sunxi/sunxi_sram.h>
32#include <linux/dmaengine.h>
33
34#include "sun4i-emac.h"
35
36#define DRV_NAME		"sun4i-emac"
37
38#define EMAC_MAX_FRAME_LEN	0x0600
39
40#define EMAC_DEFAULT_MSG_ENABLE 0x0000
41static int debug = -1;     /* defaults above */;
42module_param(debug, int, 0);
43MODULE_PARM_DESC(debug, "debug message flags");
44
45/* Transmit timeout, default 5 seconds. */
46static int watchdog = 5000;
47module_param(watchdog, int, 0400);
48MODULE_PARM_DESC(watchdog, "transmit timeout in milliseconds");
49
50/* EMAC register address locking.
51 *
52 * The EMAC uses an address register to control where data written
53 * to the data register goes. This means that the address register
54 * must be preserved over interrupts or similar calls.
55 *
56 * During interrupt and other critical calls, a spinlock is used to
57 * protect the system, but the calls themselves save the address
58 * in the address register in case they are interrupting another
59 * access to the device.
60 *
61 * For general accesses a lock is provided so that calls which are
62 * allowed to sleep are serialised so that the address register does
63 * not need to be saved. This lock also serves to serialise access
64 * to the EEPROM and PHY access registers which are shared between
65 * these two devices.
66 */
67
68/* The driver supports the original EMACE, and now the two newer
69 * devices, EMACA and EMACB.
70 */
71
72struct emac_board_info {
73	struct clk		*clk;
74	struct device		*dev;
75	struct platform_device	*pdev;
76	spinlock_t		lock;
77	void __iomem		*membase;
78	u32			msg_enable;
79	struct net_device	*ndev;
80	u16			tx_fifo_stat;
81
82	int			emacrx_completed_flag;
83
84	struct device_node	*phy_node;
85	unsigned int		link;
86	unsigned int		speed;
87	unsigned int		duplex;
88
89	phy_interface_t		phy_interface;
90	struct dma_chan	*rx_chan;
91	phys_addr_t emac_rx_fifo;
92};
93
94struct emac_dma_req {
95	struct emac_board_info *db;
96	struct dma_async_tx_descriptor *desc;
97	struct sk_buff *skb;
98	dma_addr_t rxbuf;
99	int count;
100};
101
102static void emac_update_speed(struct net_device *dev)
103{
104	struct emac_board_info *db = netdev_priv(dev);
105	unsigned int reg_val;
106
107	/* set EMAC SPEED, depend on PHY  */
108	reg_val = readl(db->membase + EMAC_MAC_SUPP_REG);
109	reg_val &= ~EMAC_MAC_SUPP_100M;
110	if (db->speed == SPEED_100)
111		reg_val |= EMAC_MAC_SUPP_100M;
112	writel(reg_val, db->membase + EMAC_MAC_SUPP_REG);
113}
114
115static void emac_update_duplex(struct net_device *dev)
116{
117	struct emac_board_info *db = netdev_priv(dev);
118	unsigned int reg_val;
119
120	/* set duplex depend on phy */
121	reg_val = readl(db->membase + EMAC_MAC_CTL1_REG);
122	reg_val &= ~EMAC_MAC_CTL1_DUPLEX_EN;
123	if (db->duplex)
124		reg_val |= EMAC_MAC_CTL1_DUPLEX_EN;
125	writel(reg_val, db->membase + EMAC_MAC_CTL1_REG);
126}
127
128static void emac_handle_link_change(struct net_device *dev)
129{
130	struct emac_board_info *db = netdev_priv(dev);
131	struct phy_device *phydev = dev->phydev;
132	unsigned long flags;
133	int status_change = 0;
134
135	if (phydev->link) {
136		if (db->speed != phydev->speed) {
137			spin_lock_irqsave(&db->lock, flags);
138			db->speed = phydev->speed;
139			emac_update_speed(dev);
140			spin_unlock_irqrestore(&db->lock, flags);
141			status_change = 1;
142		}
143
144		if (db->duplex != phydev->duplex) {
145			spin_lock_irqsave(&db->lock, flags);
146			db->duplex = phydev->duplex;
147			emac_update_duplex(dev);
148			spin_unlock_irqrestore(&db->lock, flags);
149			status_change = 1;
150		}
151	}
152
153	if (phydev->link != db->link) {
154		if (!phydev->link) {
155			db->speed = 0;
156			db->duplex = -1;
157		}
158		db->link = phydev->link;
159
160		status_change = 1;
161	}
162
163	if (status_change)
164		phy_print_status(phydev);
165}
166
167static int emac_mdio_probe(struct net_device *dev)
168{
169	struct emac_board_info *db = netdev_priv(dev);
170	struct phy_device *phydev;
171
172	/* to-do: PHY interrupts are currently not supported */
173
174	/* attach the mac to the phy */
175	phydev = of_phy_connect(db->ndev, db->phy_node,
176				&emac_handle_link_change, 0,
177				db->phy_interface);
178	if (!phydev) {
179		netdev_err(db->ndev, "could not find the PHY\n");
180		return -ENODEV;
181	}
182
183	/* mask with MAC supported features */
184	phy_set_max_speed(phydev, SPEED_100);
185
186	db->link = 0;
187	db->speed = 0;
188	db->duplex = -1;
189
190	return 0;
191}
192
193static void emac_mdio_remove(struct net_device *dev)
194{
195	phy_disconnect(dev->phydev);
196}
197
198static void emac_reset(struct emac_board_info *db)
199{
200	dev_dbg(db->dev, "resetting device\n");
201
202	/* RESET device */
203	writel(0, db->membase + EMAC_CTL_REG);
204	udelay(200);
205	writel(EMAC_CTL_RESET, db->membase + EMAC_CTL_REG);
206	udelay(200);
207}
208
209static void emac_outblk_32bit(void __iomem *reg, void *data, int count)
210{
211	writesl(reg, data, round_up(count, 4) / 4);
212}
213
214static void emac_inblk_32bit(void __iomem *reg, void *data, int count)
215{
216	readsl(reg, data, round_up(count, 4) / 4);
217}
218
219static struct emac_dma_req *
220emac_alloc_dma_req(struct emac_board_info *db,
221		   struct dma_async_tx_descriptor *desc, struct sk_buff *skb,
222		   dma_addr_t rxbuf, int count)
223{
224	struct emac_dma_req *req;
225
226	req = kzalloc(sizeof(struct emac_dma_req), GFP_ATOMIC);
227	if (!req)
228		return NULL;
229
230	req->db = db;
231	req->desc = desc;
232	req->skb = skb;
233	req->rxbuf = rxbuf;
234	req->count = count;
235	return req;
236}
237
238static void emac_free_dma_req(struct emac_dma_req *req)
239{
240	kfree(req);
241}
242
243static void emac_dma_done_callback(void *arg)
244{
245	struct emac_dma_req *req = arg;
246	struct emac_board_info *db = req->db;
247	struct sk_buff *skb = req->skb;
248	struct net_device *dev = db->ndev;
249	int rxlen = req->count;
250	u32 reg_val;
251
252	dma_unmap_single(db->dev, req->rxbuf, rxlen, DMA_FROM_DEVICE);
253
254	skb->protocol = eth_type_trans(skb, dev);
255	netif_rx(skb);
256	dev->stats.rx_bytes += rxlen;
257	/* Pass to upper layer */
258	dev->stats.rx_packets++;
259
260	/* re enable cpu receive */
261	reg_val = readl(db->membase + EMAC_RX_CTL_REG);
262	reg_val &= ~EMAC_RX_CTL_DMA_EN;
263	writel(reg_val, db->membase + EMAC_RX_CTL_REG);
264
265	/* re enable interrupt */
266	reg_val = readl(db->membase + EMAC_INT_CTL_REG);
267	reg_val |= EMAC_INT_CTL_RX_EN;
268	writel(reg_val, db->membase + EMAC_INT_CTL_REG);
269
270	db->emacrx_completed_flag = 1;
271	emac_free_dma_req(req);
272}
273
274static int emac_dma_inblk_32bit(struct emac_board_info *db,
275		struct sk_buff *skb, void *rdptr, int count)
276{
277	struct dma_async_tx_descriptor *desc;
278	dma_cookie_t cookie;
279	dma_addr_t rxbuf;
280	struct emac_dma_req *req;
281	int ret = 0;
282
283	rxbuf = dma_map_single(db->dev, rdptr, count, DMA_FROM_DEVICE);
284	ret = dma_mapping_error(db->dev, rxbuf);
285	if (ret) {
286		dev_err(db->dev, "dma mapping error.\n");
287		return ret;
288	}
289
290	desc = dmaengine_prep_slave_single(db->rx_chan, rxbuf, count,
291					   DMA_DEV_TO_MEM,
292					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
293	if (!desc) {
294		dev_err(db->dev, "prepare slave single failed\n");
295		ret = -ENOMEM;
296		goto prepare_err;
297	}
298
299	req = emac_alloc_dma_req(db, desc, skb, rxbuf, count);
300	if (!req) {
301		dev_err(db->dev, "alloc emac dma req error.\n");
302		ret = -ENOMEM;
303		goto alloc_req_err;
304	}
305
306	desc->callback_param = req;
307	desc->callback = emac_dma_done_callback;
308
309	cookie = dmaengine_submit(desc);
310	ret = dma_submit_error(cookie);
311	if (ret) {
312		dev_err(db->dev, "dma submit error.\n");
313		goto submit_err;
314	}
315
316	dma_async_issue_pending(db->rx_chan);
317	return ret;
318
319submit_err:
320	emac_free_dma_req(req);
321
322alloc_req_err:
323	dmaengine_desc_free(desc);
324
325prepare_err:
326	dma_unmap_single(db->dev, rxbuf, count, DMA_FROM_DEVICE);
327	return ret;
328}
329
330/* ethtool ops */
331static void emac_get_drvinfo(struct net_device *dev,
332			      struct ethtool_drvinfo *info)
333{
334	strscpy(info->driver, DRV_NAME, sizeof(info->driver));
335	strscpy(info->bus_info, dev_name(&dev->dev), sizeof(info->bus_info));
336}
337
338static u32 emac_get_msglevel(struct net_device *dev)
339{
340	struct emac_board_info *db = netdev_priv(dev);
341
342	return db->msg_enable;
343}
344
345static void emac_set_msglevel(struct net_device *dev, u32 value)
346{
347	struct emac_board_info *db = netdev_priv(dev);
348
349	db->msg_enable = value;
350}
351
352static const struct ethtool_ops emac_ethtool_ops = {
353	.get_drvinfo	= emac_get_drvinfo,
354	.get_link	= ethtool_op_get_link,
355	.get_link_ksettings = phy_ethtool_get_link_ksettings,
356	.set_link_ksettings = phy_ethtool_set_link_ksettings,
357	.get_msglevel	= emac_get_msglevel,
358	.set_msglevel	= emac_set_msglevel,
359};
360
361static unsigned int emac_setup(struct net_device *ndev)
362{
363	struct emac_board_info *db = netdev_priv(ndev);
364	unsigned int reg_val;
365
366	/* set up TX */
367	reg_val = readl(db->membase + EMAC_TX_MODE_REG);
368
369	writel(reg_val | EMAC_TX_MODE_ABORTED_FRAME_EN,
370		db->membase + EMAC_TX_MODE_REG);
371
372	/* set MAC */
373	/* set MAC CTL0 */
374	reg_val = readl(db->membase + EMAC_MAC_CTL0_REG);
375	writel(reg_val | EMAC_MAC_CTL0_RX_FLOW_CTL_EN |
376		EMAC_MAC_CTL0_TX_FLOW_CTL_EN,
377		db->membase + EMAC_MAC_CTL0_REG);
378
379	/* set MAC CTL1 */
380	reg_val = readl(db->membase + EMAC_MAC_CTL1_REG);
381	reg_val |= EMAC_MAC_CTL1_LEN_CHECK_EN;
382	reg_val |= EMAC_MAC_CTL1_CRC_EN;
383	reg_val |= EMAC_MAC_CTL1_PAD_EN;
384	writel(reg_val, db->membase + EMAC_MAC_CTL1_REG);
385
386	/* set up IPGT */
387	writel(EMAC_MAC_IPGT_FULL_DUPLEX, db->membase + EMAC_MAC_IPGT_REG);
388
389	/* set up IPGR */
390	writel((EMAC_MAC_IPGR_IPG1 << 8) | EMAC_MAC_IPGR_IPG2,
391		db->membase + EMAC_MAC_IPGR_REG);
392
393	/* set up Collison window */
394	writel((EMAC_MAC_CLRT_COLLISION_WINDOW << 8) | EMAC_MAC_CLRT_RM,
395		db->membase + EMAC_MAC_CLRT_REG);
396
397	/* set up Max Frame Length */
398	writel(EMAC_MAX_FRAME_LEN,
399		db->membase + EMAC_MAC_MAXF_REG);
400
401	return 0;
402}
403
404static void emac_set_rx_mode(struct net_device *ndev)
405{
406	struct emac_board_info *db = netdev_priv(ndev);
407	unsigned int reg_val;
408
409	/* set up RX */
410	reg_val = readl(db->membase + EMAC_RX_CTL_REG);
411
412	if (ndev->flags & IFF_PROMISC)
413		reg_val |= EMAC_RX_CTL_PASS_ALL_EN;
414	else
415		reg_val &= ~EMAC_RX_CTL_PASS_ALL_EN;
416
417	writel(reg_val | EMAC_RX_CTL_PASS_LEN_OOR_EN |
418		EMAC_RX_CTL_ACCEPT_UNICAST_EN | EMAC_RX_CTL_DA_FILTER_EN |
419		EMAC_RX_CTL_ACCEPT_MULTICAST_EN |
420		EMAC_RX_CTL_ACCEPT_BROADCAST_EN,
421		db->membase + EMAC_RX_CTL_REG);
422}
423
424static unsigned int emac_powerup(struct net_device *ndev)
425{
426	struct emac_board_info *db = netdev_priv(ndev);
427	unsigned int reg_val;
428
429	/* initial EMAC */
430	/* flush RX FIFO */
431	reg_val = readl(db->membase + EMAC_RX_CTL_REG);
432	reg_val |= EMAC_RX_CTL_FLUSH_FIFO;
433	writel(reg_val, db->membase + EMAC_RX_CTL_REG);
434	udelay(1);
435
436	/* initial MAC */
437	/* soft reset MAC */
438	reg_val = readl(db->membase + EMAC_MAC_CTL0_REG);
439	reg_val &= ~EMAC_MAC_CTL0_SOFT_RESET;
440	writel(reg_val, db->membase + EMAC_MAC_CTL0_REG);
441
442	/* set MII clock */
443	reg_val = readl(db->membase + EMAC_MAC_MCFG_REG);
444	reg_val &= ~EMAC_MAC_MCFG_MII_CLKD_MASK;
445	reg_val |= EMAC_MAC_MCFG_MII_CLKD_72;
446	writel(reg_val, db->membase + EMAC_MAC_MCFG_REG);
447
448	/* clear RX counter */
449	writel(0x0, db->membase + EMAC_RX_FBC_REG);
450
451	/* disable all interrupt and clear interrupt status */
452	writel(0, db->membase + EMAC_INT_CTL_REG);
453	reg_val = readl(db->membase + EMAC_INT_STA_REG);
454	writel(reg_val, db->membase + EMAC_INT_STA_REG);
455
456	udelay(1);
457
458	/* set up EMAC */
459	emac_setup(ndev);
460
461	/* set mac_address to chip */
462	writel(ndev->dev_addr[0] << 16 | ndev->dev_addr[1] << 8 | ndev->
463	       dev_addr[2], db->membase + EMAC_MAC_A1_REG);
464	writel(ndev->dev_addr[3] << 16 | ndev->dev_addr[4] << 8 | ndev->
465	       dev_addr[5], db->membase + EMAC_MAC_A0_REG);
466
467	mdelay(1);
468
469	return 0;
470}
471
472static int emac_set_mac_address(struct net_device *dev, void *p)
473{
474	struct sockaddr *addr = p;
475	struct emac_board_info *db = netdev_priv(dev);
476
477	if (netif_running(dev))
478		return -EBUSY;
479
480	eth_hw_addr_set(dev, addr->sa_data);
481
482	writel(dev->dev_addr[0] << 16 | dev->dev_addr[1] << 8 | dev->
483	       dev_addr[2], db->membase + EMAC_MAC_A1_REG);
484	writel(dev->dev_addr[3] << 16 | dev->dev_addr[4] << 8 | dev->
485	       dev_addr[5], db->membase + EMAC_MAC_A0_REG);
486
487	return 0;
488}
489
490/* Initialize emac board */
491static void emac_init_device(struct net_device *dev)
492{
493	struct emac_board_info *db = netdev_priv(dev);
494	unsigned long flags;
495	unsigned int reg_val;
496
497	spin_lock_irqsave(&db->lock, flags);
498
499	emac_update_speed(dev);
500	emac_update_duplex(dev);
501
502	/* enable RX/TX */
503	reg_val = readl(db->membase + EMAC_CTL_REG);
504	writel(reg_val | EMAC_CTL_RESET | EMAC_CTL_TX_EN | EMAC_CTL_RX_EN,
505		db->membase + EMAC_CTL_REG);
506
507	/* enable RX/TX0/RX Hlevel interrup */
508	reg_val = readl(db->membase + EMAC_INT_CTL_REG);
509	reg_val |= (EMAC_INT_CTL_TX_EN | EMAC_INT_CTL_TX_ABRT_EN | EMAC_INT_CTL_RX_EN);
510	writel(reg_val, db->membase + EMAC_INT_CTL_REG);
511
512	spin_unlock_irqrestore(&db->lock, flags);
513}
514
515/* Our watchdog timed out. Called by the networking layer */
516static void emac_timeout(struct net_device *dev, unsigned int txqueue)
517{
518	struct emac_board_info *db = netdev_priv(dev);
519	unsigned long flags;
520
521	if (netif_msg_timer(db))
522		dev_err(db->dev, "tx time out.\n");
523
524	/* Save previous register address */
525	spin_lock_irqsave(&db->lock, flags);
526
527	netif_stop_queue(dev);
528	emac_reset(db);
529	emac_init_device(dev);
530	/* We can accept TX packets again */
531	netif_trans_update(dev);
532	netif_wake_queue(dev);
533
534	/* Restore previous register address */
535	spin_unlock_irqrestore(&db->lock, flags);
536}
537
538/* Hardware start transmission.
539 * Send a packet to media from the upper layer.
540 */
541static netdev_tx_t emac_start_xmit(struct sk_buff *skb, struct net_device *dev)
542{
543	struct emac_board_info *db = netdev_priv(dev);
544	unsigned long channel;
545	unsigned long flags;
546
547	channel = db->tx_fifo_stat & 3;
548	if (channel == 3)
549		return NETDEV_TX_BUSY;
550
551	channel = (channel == 1 ? 1 : 0);
552
553	spin_lock_irqsave(&db->lock, flags);
554
555	writel(channel, db->membase + EMAC_TX_INS_REG);
556
557	emac_outblk_32bit(db->membase + EMAC_TX_IO_DATA_REG,
558			skb->data, skb->len);
559	dev->stats.tx_bytes += skb->len;
560
561	db->tx_fifo_stat |= 1 << channel;
562	/* TX control: First packet immediately send, second packet queue */
563	if (channel == 0) {
564		/* set TX len */
565		writel(skb->len, db->membase + EMAC_TX_PL0_REG);
566		/* start translate from fifo to phy */
567		writel(readl(db->membase + EMAC_TX_CTL0_REG) | 1,
568		       db->membase + EMAC_TX_CTL0_REG);
569
570		/* save the time stamp */
571		netif_trans_update(dev);
572	} else if (channel == 1) {
573		/* set TX len */
574		writel(skb->len, db->membase + EMAC_TX_PL1_REG);
575		/* start translate from fifo to phy */
576		writel(readl(db->membase + EMAC_TX_CTL1_REG) | 1,
577		       db->membase + EMAC_TX_CTL1_REG);
578
579		/* save the time stamp */
580		netif_trans_update(dev);
581	}
582
583	if ((db->tx_fifo_stat & 3) == 3) {
584		/* Second packet */
585		netif_stop_queue(dev);
586	}
587
588	spin_unlock_irqrestore(&db->lock, flags);
589
590	/* free this SKB */
591	dev_consume_skb_any(skb);
592
593	return NETDEV_TX_OK;
594}
595
596/* EMAC interrupt handler
597 * receive the packet to upper layer, free the transmitted packet
598 */
599static void emac_tx_done(struct net_device *dev, struct emac_board_info *db,
600			  unsigned int tx_status)
601{
602	/* One packet sent complete */
603	db->tx_fifo_stat &= ~(tx_status & 3);
604	if (3 == (tx_status & 3))
605		dev->stats.tx_packets += 2;
606	else
607		dev->stats.tx_packets++;
608
609	if (netif_msg_tx_done(db))
610		dev_dbg(db->dev, "tx done, NSR %02x\n", tx_status);
611
612	netif_wake_queue(dev);
613}
614
615/* Received a packet and pass to upper layer
616 */
617static void emac_rx(struct net_device *dev)
618{
619	struct emac_board_info *db = netdev_priv(dev);
620	struct sk_buff *skb;
621	u8 *rdptr;
622	bool good_packet;
623	unsigned int reg_val;
624	u32 rxhdr, rxstatus, rxcount, rxlen;
625
626	/* Check packet ready or not */
627	while (1) {
628		/* race warning: the first packet might arrive with
629		 * the interrupts disabled, but the second will fix
630		 * it
631		 */
632		rxcount = readl(db->membase + EMAC_RX_FBC_REG);
633
634		if (netif_msg_rx_status(db))
635			dev_dbg(db->dev, "RXCount: %x\n", rxcount);
636
637		if (!rxcount) {
638			db->emacrx_completed_flag = 1;
639			reg_val = readl(db->membase + EMAC_INT_CTL_REG);
640			reg_val |= (EMAC_INT_CTL_TX_EN |
641					EMAC_INT_CTL_TX_ABRT_EN |
642					EMAC_INT_CTL_RX_EN);
643			writel(reg_val, db->membase + EMAC_INT_CTL_REG);
644
645			/* had one stuck? */
646			rxcount = readl(db->membase + EMAC_RX_FBC_REG);
647			if (!rxcount)
648				return;
649		}
650
651		reg_val = readl(db->membase + EMAC_RX_IO_DATA_REG);
652		if (netif_msg_rx_status(db))
653			dev_dbg(db->dev, "receive header: %x\n", reg_val);
654		if (reg_val != EMAC_UNDOCUMENTED_MAGIC) {
655			/* disable RX */
656			reg_val = readl(db->membase + EMAC_CTL_REG);
657			writel(reg_val & ~EMAC_CTL_RX_EN,
658			       db->membase + EMAC_CTL_REG);
659
660			/* Flush RX FIFO */
661			reg_val = readl(db->membase + EMAC_RX_CTL_REG);
662			writel(reg_val | (1 << 3),
663			       db->membase + EMAC_RX_CTL_REG);
664
665			do {
666				reg_val = readl(db->membase + EMAC_RX_CTL_REG);
667			} while (reg_val & (1 << 3));
668
669			/* enable RX */
670			reg_val = readl(db->membase + EMAC_CTL_REG);
671			writel(reg_val | EMAC_CTL_RX_EN,
672			       db->membase + EMAC_CTL_REG);
673			reg_val = readl(db->membase + EMAC_INT_CTL_REG);
674			reg_val |= (EMAC_INT_CTL_TX_EN |
675					EMAC_INT_CTL_TX_ABRT_EN |
676					EMAC_INT_CTL_RX_EN);
677			writel(reg_val, db->membase + EMAC_INT_CTL_REG);
678
679			db->emacrx_completed_flag = 1;
680
681			return;
682		}
683
684		/* A packet ready now  & Get status/length */
685		good_packet = true;
686
687		rxhdr = readl(db->membase + EMAC_RX_IO_DATA_REG);
688
689		if (netif_msg_rx_status(db))
690			dev_dbg(db->dev, "rxhdr: %x\n", *((int *)(&rxhdr)));
691
692		rxlen = EMAC_RX_IO_DATA_LEN(rxhdr);
693		rxstatus = EMAC_RX_IO_DATA_STATUS(rxhdr);
694
695		if (netif_msg_rx_status(db))
696			dev_dbg(db->dev, "RX: status %02x, length %04x\n",
697				rxstatus, rxlen);
698
699		/* Packet Status check */
700		if (rxlen < 0x40) {
701			good_packet = false;
702			if (netif_msg_rx_err(db))
703				dev_dbg(db->dev, "RX: Bad Packet (runt)\n");
704		}
705
706		if (unlikely(!(rxstatus & EMAC_RX_IO_DATA_STATUS_OK))) {
707			good_packet = false;
708
709			if (rxstatus & EMAC_RX_IO_DATA_STATUS_CRC_ERR) {
710				if (netif_msg_rx_err(db))
711					dev_dbg(db->dev, "crc error\n");
712				dev->stats.rx_crc_errors++;
713			}
714
715			if (rxstatus & EMAC_RX_IO_DATA_STATUS_LEN_ERR) {
716				if (netif_msg_rx_err(db))
717					dev_dbg(db->dev, "length error\n");
718				dev->stats.rx_length_errors++;
719			}
720		}
721
722		/* Move data from EMAC */
723		if (good_packet) {
724			skb = netdev_alloc_skb(dev, rxlen + 4);
725			if (!skb)
726				continue;
727			skb_reserve(skb, 2);
728			rdptr = skb_put(skb, rxlen - 4);
729
730			/* Read received packet from RX SRAM */
731			if (netif_msg_rx_status(db))
732				dev_dbg(db->dev, "RxLen %x\n", rxlen);
733
734			if (rxlen >= dev->mtu && db->rx_chan) {
735				reg_val = readl(db->membase + EMAC_RX_CTL_REG);
736				reg_val |= EMAC_RX_CTL_DMA_EN;
737				writel(reg_val, db->membase + EMAC_RX_CTL_REG);
738				if (!emac_dma_inblk_32bit(db, skb, rdptr, rxlen))
739					break;
740
741				/* re enable cpu receive. then try to receive by emac_inblk_32bit */
742				reg_val = readl(db->membase + EMAC_RX_CTL_REG);
743				reg_val &= ~EMAC_RX_CTL_DMA_EN;
744				writel(reg_val, db->membase + EMAC_RX_CTL_REG);
745			}
746
747			emac_inblk_32bit(db->membase + EMAC_RX_IO_DATA_REG,
748					rdptr, rxlen);
749			dev->stats.rx_bytes += rxlen;
750
751			/* Pass to upper layer */
752			skb->protocol = eth_type_trans(skb, dev);
753			netif_rx(skb);
754			dev->stats.rx_packets++;
755		}
756	}
757}
758
759static irqreturn_t emac_interrupt(int irq, void *dev_id)
760{
761	struct net_device *dev = dev_id;
762	struct emac_board_info *db = netdev_priv(dev);
763	int int_status;
764	unsigned int reg_val;
765
766	/* A real interrupt coming */
767
768	spin_lock(&db->lock);
769
770	/* Disable all interrupts */
771	writel(0, db->membase + EMAC_INT_CTL_REG);
772
773	/* Got EMAC interrupt status */
774	/* Got ISR */
775	int_status = readl(db->membase + EMAC_INT_STA_REG);
776	/* Clear ISR status */
777	writel(int_status, db->membase + EMAC_INT_STA_REG);
778
779	if (netif_msg_intr(db))
780		dev_dbg(db->dev, "emac interrupt %02x\n", int_status);
781
782	/* Received the coming packet */
783	if ((int_status & 0x100) && (db->emacrx_completed_flag == 1)) {
784		/* carrier lost */
785		db->emacrx_completed_flag = 0;
786		emac_rx(dev);
787	}
788
789	/* Transmit Interrupt check */
790	if (int_status & EMAC_INT_STA_TX_COMPLETE)
791		emac_tx_done(dev, db, int_status);
792
793	if (int_status & EMAC_INT_STA_TX_ABRT)
794		netdev_info(dev, " ab : %x\n", int_status);
795
796	/* Re-enable interrupt mask */
797	if (db->emacrx_completed_flag == 1) {
798		reg_val = readl(db->membase + EMAC_INT_CTL_REG);
799		reg_val |= (EMAC_INT_CTL_TX_EN | EMAC_INT_CTL_TX_ABRT_EN | EMAC_INT_CTL_RX_EN);
800		writel(reg_val, db->membase + EMAC_INT_CTL_REG);
801	} else {
802		reg_val = readl(db->membase + EMAC_INT_CTL_REG);
803		reg_val |= (EMAC_INT_CTL_TX_EN | EMAC_INT_CTL_TX_ABRT_EN);
804		writel(reg_val, db->membase + EMAC_INT_CTL_REG);
805	}
806
807	spin_unlock(&db->lock);
808
809	return IRQ_HANDLED;
810}
811
812#ifdef CONFIG_NET_POLL_CONTROLLER
813/*
814 * Used by netconsole
815 */
816static void emac_poll_controller(struct net_device *dev)
817{
818	disable_irq(dev->irq);
819	emac_interrupt(dev->irq, dev);
820	enable_irq(dev->irq);
821}
822#endif
823
824/*  Open the interface.
825 *  The interface is opened whenever "ifconfig" actives it.
826 */
827static int emac_open(struct net_device *dev)
828{
829	struct emac_board_info *db = netdev_priv(dev);
830	int ret;
831
832	if (netif_msg_ifup(db))
833		dev_dbg(db->dev, "enabling %s\n", dev->name);
834
835	if (request_irq(dev->irq, &emac_interrupt, 0, dev->name, dev))
836		return -EAGAIN;
837
838	/* Initialize EMAC board */
839	emac_reset(db);
840	emac_init_device(dev);
841
842	ret = emac_mdio_probe(dev);
843	if (ret < 0) {
844		free_irq(dev->irq, dev);
845		netdev_err(dev, "cannot probe MDIO bus\n");
846		return ret;
847	}
848
849	phy_start(dev->phydev);
850	netif_start_queue(dev);
851
852	return 0;
853}
854
855static void emac_shutdown(struct net_device *dev)
856{
857	unsigned int reg_val;
858	struct emac_board_info *db = netdev_priv(dev);
859
860	/* Disable all interrupt */
861	writel(0, db->membase + EMAC_INT_CTL_REG);
862
863	/* clear interrupt status */
864	reg_val = readl(db->membase + EMAC_INT_STA_REG);
865	writel(reg_val, db->membase + EMAC_INT_STA_REG);
866
867	/* Disable RX/TX */
868	reg_val = readl(db->membase + EMAC_CTL_REG);
869	reg_val &= ~(EMAC_CTL_TX_EN | EMAC_CTL_RX_EN | EMAC_CTL_RESET);
870	writel(reg_val, db->membase + EMAC_CTL_REG);
871}
872
873/* Stop the interface.
874 * The interface is stopped when it is brought.
875 */
876static int emac_stop(struct net_device *ndev)
877{
878	struct emac_board_info *db = netdev_priv(ndev);
879
880	if (netif_msg_ifdown(db))
881		dev_dbg(db->dev, "shutting down %s\n", ndev->name);
882
883	netif_stop_queue(ndev);
884	netif_carrier_off(ndev);
885
886	phy_stop(ndev->phydev);
887
888	emac_mdio_remove(ndev);
889
890	emac_shutdown(ndev);
891
892	free_irq(ndev->irq, ndev);
893
894	return 0;
895}
896
897static const struct net_device_ops emac_netdev_ops = {
898	.ndo_open		= emac_open,
899	.ndo_stop		= emac_stop,
900	.ndo_start_xmit		= emac_start_xmit,
901	.ndo_tx_timeout		= emac_timeout,
902	.ndo_set_rx_mode	= emac_set_rx_mode,
903	.ndo_eth_ioctl		= phy_do_ioctl_running,
904	.ndo_validate_addr	= eth_validate_addr,
905	.ndo_set_mac_address	= emac_set_mac_address,
906#ifdef CONFIG_NET_POLL_CONTROLLER
907	.ndo_poll_controller	= emac_poll_controller,
908#endif
909};
910
911static int emac_configure_dma(struct emac_board_info *db)
912{
913	struct platform_device *pdev = db->pdev;
914	struct net_device *ndev = db->ndev;
915	struct dma_slave_config conf = {};
916	struct resource *regs;
917	int err = 0;
918
919	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
920	if (!regs) {
921		netdev_err(ndev, "get io resource from device failed.\n");
922		err = -ENOMEM;
923		goto out_clear_chan;
924	}
925
926	netdev_info(ndev, "get io resource from device: %pa, size = %u\n",
927		    &regs->start, (unsigned int)resource_size(regs));
928	db->emac_rx_fifo = regs->start + EMAC_RX_IO_DATA_REG;
929
930	db->rx_chan = dma_request_chan(&pdev->dev, "rx");
931	if (IS_ERR(db->rx_chan)) {
932		netdev_err(ndev,
933			   "failed to request dma channel. dma is disabled\n");
934		err = PTR_ERR(db->rx_chan);
935		goto out_clear_chan;
936	}
937
938	conf.direction = DMA_DEV_TO_MEM;
939	conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
940	conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
941	conf.src_addr = db->emac_rx_fifo;
942	conf.dst_maxburst = 4;
943	conf.src_maxburst = 4;
944	conf.device_fc = false;
945
946	err = dmaengine_slave_config(db->rx_chan, &conf);
947	if (err) {
948		netdev_err(ndev, "config dma slave failed\n");
949		err = -EINVAL;
950		goto out_slave_configure_err;
951	}
952
953	return err;
954
955out_slave_configure_err:
956	dma_release_channel(db->rx_chan);
957
958out_clear_chan:
959	db->rx_chan = NULL;
960	return err;
961}
962
963/* Search EMAC board, allocate space and register it
964 */
965static int emac_probe(struct platform_device *pdev)
966{
967	struct device_node *np = pdev->dev.of_node;
968	struct emac_board_info *db;
969	struct net_device *ndev;
970	int ret = 0;
971
972	ndev = alloc_etherdev(sizeof(struct emac_board_info));
973	if (!ndev) {
974		dev_err(&pdev->dev, "could not allocate device.\n");
975		return -ENOMEM;
976	}
977
978	SET_NETDEV_DEV(ndev, &pdev->dev);
979
980	db = netdev_priv(ndev);
981
982	db->dev = &pdev->dev;
983	db->ndev = ndev;
984	db->pdev = pdev;
985	db->msg_enable = netif_msg_init(debug, EMAC_DEFAULT_MSG_ENABLE);
986
987	spin_lock_init(&db->lock);
988
989	db->membase = of_iomap(np, 0);
990	if (!db->membase) {
991		dev_err(&pdev->dev, "failed to remap registers\n");
992		ret = -ENOMEM;
993		goto out;
994	}
995
996	/* fill in parameters for net-dev structure */
997	ndev->base_addr = (unsigned long)db->membase;
998	ndev->irq = irq_of_parse_and_map(np, 0);
999	if (ndev->irq == -ENXIO) {
1000		netdev_err(ndev, "No irq resource\n");
1001		ret = ndev->irq;
1002		goto out_iounmap;
1003	}
1004
1005	if (emac_configure_dma(db))
1006		netdev_info(ndev, "configure dma failed. disable dma.\n");
1007
1008	db->clk = devm_clk_get(&pdev->dev, NULL);
1009	if (IS_ERR(db->clk)) {
1010		ret = PTR_ERR(db->clk);
1011		goto out_dispose_mapping;
1012	}
1013
1014	ret = clk_prepare_enable(db->clk);
1015	if (ret) {
1016		dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", ret);
1017		goto out_dispose_mapping;
1018	}
1019
1020	ret = sunxi_sram_claim(&pdev->dev);
1021	if (ret) {
1022		dev_err(&pdev->dev, "Error couldn't map SRAM to device\n");
1023		goto out_clk_disable_unprepare;
1024	}
1025
1026	db->phy_node = of_parse_phandle(np, "phy-handle", 0);
1027	if (!db->phy_node)
1028		db->phy_node = of_parse_phandle(np, "phy", 0);
1029	if (!db->phy_node) {
1030		dev_err(&pdev->dev, "no associated PHY\n");
1031		ret = -ENODEV;
1032		goto out_release_sram;
1033	}
1034
1035	/* Read MAC-address from DT */
1036	ret = of_get_ethdev_address(np, ndev);
1037	if (ret) {
1038		/* if the MAC address is invalid get a random one */
1039		eth_hw_addr_random(ndev);
1040		dev_warn(&pdev->dev, "using random MAC address %pM\n",
1041			 ndev->dev_addr);
1042	}
1043
1044	db->emacrx_completed_flag = 1;
1045	emac_powerup(ndev);
1046	emac_reset(db);
1047
1048	ndev->netdev_ops = &emac_netdev_ops;
1049	ndev->watchdog_timeo = msecs_to_jiffies(watchdog);
1050	ndev->ethtool_ops = &emac_ethtool_ops;
1051
1052	platform_set_drvdata(pdev, ndev);
1053
1054	/* Carrier starts down, phylib will bring it up */
1055	netif_carrier_off(ndev);
1056
1057	ret = register_netdev(ndev);
1058	if (ret) {
1059		dev_err(&pdev->dev, "Registering netdev failed!\n");
1060		ret = -ENODEV;
1061		goto out_release_sram;
1062	}
1063
1064	dev_info(&pdev->dev, "%s: at %p, IRQ %d MAC: %pM\n",
1065		 ndev->name, db->membase, ndev->irq, ndev->dev_addr);
1066
1067	return 0;
1068
1069out_release_sram:
1070	sunxi_sram_release(&pdev->dev);
1071out_clk_disable_unprepare:
1072	clk_disable_unprepare(db->clk);
1073out_dispose_mapping:
1074	irq_dispose_mapping(ndev->irq);
1075	dma_release_channel(db->rx_chan);
1076out_iounmap:
1077	iounmap(db->membase);
1078out:
1079	dev_err(db->dev, "not found (%d).\n", ret);
1080
1081	free_netdev(ndev);
1082
1083	return ret;
1084}
1085
1086static int emac_remove(struct platform_device *pdev)
1087{
1088	struct net_device *ndev = platform_get_drvdata(pdev);
1089	struct emac_board_info *db = netdev_priv(ndev);
1090
1091	if (db->rx_chan) {
1092		dmaengine_terminate_all(db->rx_chan);
1093		dma_release_channel(db->rx_chan);
1094	}
1095
1096	unregister_netdev(ndev);
1097	sunxi_sram_release(&pdev->dev);
1098	clk_disable_unprepare(db->clk);
1099	irq_dispose_mapping(ndev->irq);
1100	iounmap(db->membase);
1101	free_netdev(ndev);
1102
1103	dev_dbg(&pdev->dev, "released and freed device\n");
1104	return 0;
1105}
1106
1107static int emac_suspend(struct platform_device *dev, pm_message_t state)
1108{
1109	struct net_device *ndev = platform_get_drvdata(dev);
1110
1111	netif_carrier_off(ndev);
1112	netif_device_detach(ndev);
1113	emac_shutdown(ndev);
1114
1115	return 0;
1116}
1117
1118static int emac_resume(struct platform_device *dev)
1119{
1120	struct net_device *ndev = platform_get_drvdata(dev);
1121	struct emac_board_info *db = netdev_priv(ndev);
1122
1123	emac_reset(db);
1124	emac_init_device(ndev);
1125	netif_device_attach(ndev);
1126
1127	return 0;
1128}
1129
1130static const struct of_device_id emac_of_match[] = {
1131	{.compatible = "allwinner,sun4i-a10-emac",},
1132
1133	/* Deprecated */
1134	{.compatible = "allwinner,sun4i-emac",},
1135	{},
1136};
1137
1138MODULE_DEVICE_TABLE(of, emac_of_match);
1139
1140static struct platform_driver emac_driver = {
1141	.driver = {
1142		.name = "sun4i-emac",
1143		.of_match_table = emac_of_match,
1144	},
1145	.probe = emac_probe,
1146	.remove = emac_remove,
1147	.suspend = emac_suspend,
1148	.resume = emac_resume,
1149};
1150
1151module_platform_driver(emac_driver);
1152
1153MODULE_AUTHOR("Stefan Roese <sr@denx.de>");
1154MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1155MODULE_DESCRIPTION("Allwinner A10 emac network driver");
1156MODULE_LICENSE("GPL");
1157